Goto Chockstone Home

  Guide
  Gallery
  Tech Tips
  Articles
  Reviews
  Dictionary
  Links
  Forum
  Search
  About

      Sponsored By
      ROCK
   HARDWARE

  Shop
FREIGHT FREE
in Australia

Black Diamond: "Vario Speed Harness" Classic. One side fits all. Large (pre-threaded) quick-adjsut buckles. Wide nylon webbing. (Recommended for Gym use) SUPER SPECIAL!!!  $59.00
26% Off

Chockstone Photography Australian Landscape Photography by Michael Boniwell
Australian Landscape Prints





Chockstone Forum - Climbing Videos

Post links and comments about your favourite climbing flicks

 Page 2 of 2. Messages 1 to 20 | 21 to 39
Author
OT - Probably the most crazy man in the world

shortman
16/12/2011
1:15:39 PM
On 16/12/2011 ajfclark wrote:
>Is Dwain the guy that hit the bridge?

Yep, because he misjudged his descent, not cause he stalled.

shortman
16/12/2011
1:17:53 PM
On 16/12/2011 J.C. wrote:
>hey shortman, not sure where you are getting your info but after a few
>seconds in a wingsuit you are indeed flying, albeit only at a glide ratio
>of give or take 3:1, so check your BAK books again because i can assure
>you that it isnt hard to stall a suit if you are flying too flat/slow or
>you have bad body position. for a more 'real life' example, ask Dwain Weston
>about stalling suits if you bump into him.
>as far as the wonderful notion of just gliding along a slope and touching
>down gently (yes we've all dreamed!), you would still be touching down
>at 250km/h or so on your stomach, head first, with 1mm of nylon for protection.
>no thanks! :)

I still can't see how u would stall without thrust.

Certainly you could adjust your speed, to the point where u would start to tumble, but not a complete stall, otherwise the landing would have happened by now.
>
widewetandslippery
16/12/2011
1:27:43 PM
I think its all about0arms in. Arms out. Changes the wingsuite. Function
davepalethorpe
16/12/2011
1:51:42 PM
>
>I still can't see how u would stall without thrust.
>>

When you increase the angle of attack of the wing, the lift it generates increases, until it reaches a point whereby any further increase in the angle of attack actually reduces the lift generated. This is the point of "stall". Doesn't matter about thrust unless you want to stop falling!

shortman
16/12/2011
10:13:31 PM
On 16/12/2011 davepalethorpe wrote:

>When you increase the angle of attack of the wing, the lift it generates
>increases, until it reaches a point whereby any further increase in the
>angle of attack actually reduces the lift generated. This is the point
>of "stall". Doesn't matter about thrust unless you want to stop falling!

So at a 3:1 ratio capacity, (which is 3m forwards to 1m dropping) where can the power come from to stop mid air? How could the human body in a wingsuit get to the angle of attack? It can't.

From the aerospace article and Jeb himself:

"He’s got lift, for sure, but he’ll be traveling at more than 100 mph, dropping a foot for every three feet forward. It’s the maximum glide angle, and one at which he can’t get more lift; he can’t suddenly flare up while screaming in toward a landing. “An airplane comes in at a certain approach speed and the pilot pulls the stick back and flares, and that neutralizes the sink rate,” says Mark Maughmer, a professor of aerospace engineering at Pennsylvania State University. “You’re trading the airspeed you have, its kinetic energy, into potential lift for a moment.” But Corliss will have precious little flare. Which is why wing suit fliers on proxy flights don’t, in fact, go for maximum glide angle, so they have a little something in reserve in case they need to swoop over and away from objects. Corliss, then, will travel even faster, and that’s the essence of the challenge: Come in for a landing so fast with so little lift that his abort options are extremely limited."

"Corliss has a very specific goal, and it’s not only to land without a chute, but to land at high speed and to do it in a wing suit that has no additional appendages. “I’m not interested in anything with a rigid wing, and I don’t want anything with a 7:1 glide ratio.” If some other flier beats him, he says, it will be on that snow-covered mountain “by someone who doesn’t worry about the consequences. But to me that act has a 1-in-10 chance of success, and that’s too risky. I want to do it over and over again and walk away each time."

Robert Pecnik, the wing suit maker, appreciates Corliss’ desire to use only a standard wing suit, but the endeavor itself makes him nervous. “The human body is not designed to fly,” he says. “It takes a stronger and stronger effort to succeed very little. Better wing suit technology will push us to a 1:4 glide ratio...."

I think what he does is friggen awesome, I'm jealous because I know I don't have the balls, but it still aint' flyin.

Jeb himself says:

“Flying in a wing suit is that dream!” says Jeb Corliss. “It’s the closest you can come to real human flight.”

He is not confused about what he is doing.
davepalethorpe
17/12/2011
12:32:27 AM
The angle of attack is just the angle at which the aerofoil (wing) is positioned in relation to the air that hits it. What is the issue here, is that the aerofoil cannot generate enough lift to overcome the weight of the body. Hence even at maximum lift, you are still falling 1m for every 3m you are traveling forwards. I'm no mathematician, but hypothetically say you are traveling at 210km/hr, you would hit the ground with a vertical speed of nearly 70km/hr. That's a pretty quick speed to hit the ground.

I would love to see if this dream ever becomes reality....

I was having a flip through some of the wing suit vids on YouTube...crazy stuff!
J.C.
19/12/2011
5:50:58 PM
Having reviewed that footage (the full version incl impact) of Dwain many times over, frame by frame, including in the company of other more experienced wingsuit flyers and wingsuit instructors including people who regularly jumped with him, I can assure you that he was stalling the f--- out of his suit otherwise he would have cleared the bridge. Let me know when you want to come for a jump and I'll show you what a stall is. Or you can show me, rather ;)

shortman
19/12/2011
6:04:48 PM
On 19/12/2011 J.C. wrote:
>Having reviewed that footage (the full version incl impact) of Dwain many
>times over, frame by frame, including in the company of other more experienced
>wingsuit flyers and wingsuit instructors including people who regularly
>jumped with him, I can assure you that he was stalling the f--- out of
>his suit otherwise he would have cleared the bridge. Let me know when you
>want to come for a jump and I'll show you what a stall is. Or you can show
>me, rather ;)

I'll take your word for it. All I was saying was that u couldn't stall to a stop and magically land somewhere.

mattjr
19/12/2011
6:27:50 PM
Dang, I knew there was a reason I didn't actually jump out my 3rd floor bedroom window whilst sporting a chicken suit.
J.C.
19/12/2011
8:23:43 PM
Stalling a wing means that it is no longer creating lift, not that you suddenly magically stop obeying the laws of gravity & motion.

shortman
19/12/2011
9:17:43 PM
thanku

Out of interest, what happens when u stall? Do u stop going forward, but keep goin down? And how hard is it to right yourself?

IdratherbeclimbingM9
19/12/2011
9:28:44 PM
On 19/12/2011 J.C. wrote:
>Having reviewed that footage (the full version incl impact) of Dwain many
>times over, frame by frame, including in the company of other more experienced
>wingsuit flyers and wingsuit instructors including people who regularly
>jumped with him, I can assure you that he was stalling the f--- out of
>his suit otherwise he would have cleared the bridge.

It makes a novice bystander such as myself wonder why he was doing that.
If he got his approach so snafu'd (?), with his experience why did he not recognise that earlier and change trajectory to simply go under the bridge, or worst case scenario, try to shoot the gap between cables?
J.C.
19/12/2011
11:13:50 PM
I didn't know Dwain personally but from what I can gather having talked to and jumped with a bunch of folks who knew him, he was very very good at what he did (ie. very balls out aerials and LOW openings) but not as accomplished in a wingsuit. it would seem that he was trying to push boundaries in a wingsuit without the flying experience to really understand the suit.
ill spare the chockstone audience my technical observations but in a nutshell he appeared to be flying a high line then sinking towards his proximity line by flying inefficiently, rather than flying an appropriate trajectory from the start. this is never going to work (ive tried to defy basic aerodynamics in exactly the same way myself, approaching atmonauti formations in the sky.. it never works, but i had 10,000ft of air under the formation not a bridge) so he needed to be flying much steeper in the suit with arms swept further back & he needed to plan a much more suitable trajectory from WAY before he got to the bridge


ps. if you have no idea what atmonauti is, its basically flying your body to navigate a route through the sky. heres a few of the sydney boys (and girls) with a mixture of atmo and head down flying at picton recently.. http://vimeo.com/32653205
J.C.
19/12/2011
11:23:00 PM
On 19/12/2011 shortman wrote:
>thanku
>
>Out of interest, what happens when u stall? Do u stop going forward, but
>keep goin down? And how hard is it to right yourself?

if you stall the suit out you'll probably keep going forward to a limited extent from momentum and the flow of air over your body but you will basically stop flying and start falling. depending on how badly you stalled and why you did so it can eat up a lot of altitude to get flying well again

tnd
20/12/2011
9:32:37 AM
On 19/12/2011 shortman wrote:
>thanku
>
>Out of interest, what happens when u stall? Do u stop going forward, but
>keep goin down? And how hard is it to right yourself?

Aeronautics is complex, but...stalling a wing is dependent on angle of attack (the angle between the horizontal and the plane of the wing). When you reach the stall angle of attack, the wing stops flying. Your speed and direction the instant after the stall is the same as those the instant before the stall; but after the stall you're not flying, you're falling, so your subsequent path will be a curving descent towards the earth under the pull of gravity. To start flying again you have to decrease the angle of attack, i.e. tip the wing forward. If you have enough height and there isn't something solid in your way.

I would guess the stall speed (the speed at which a gentle increase of the angle of attack will get to the stall angle) of these wing suits is pretty high due to their tiny wing area and swept back profile, so when stalled they're still carrying a lot of momentum - way too much to stall them onto a vertical face as suggested above.

When you see birds "stall" onto a tree branch or ledge, they actually don't, they flap their wings a little to brake themselves. Hang gliders pretty well stall onto the ground when landing, but at very low speed so as to avoid injury. Mostly.

Personally I only fly things that I can sit inside.

IdratherbeclimbingM9
20/12/2011
11:11:54 AM
On 19/12/2011 J.C. wrote:
>heres a few of the sydney boys (and girls) with a mixture of atmo and head down flying at picton recently.. http://vimeo.com/32653205

Thanks for the link. It was good to see how that game is progressing.
For me it was also interesting to see the Picton (Wilton) landscape from above again, as that is where I did my jumping, but this was back before the freeway was built and the Hume Hwy was just a single lane in either direction in most places those days...

Wiki has some interesting reading on the subject of wingsuit flying, base jumping and related things.

Something I had heard of, but did not know the significance of, was Dean Potters wisbase record making jump from the Eiger.

The longest verified WiSBASE jump is 5.8 km (3.6 mi) by Dean Potter[21] in August, 2009. Potter jumped from Eiger and had spent 2 minutes and 50 seconds in flight, covering 7,900 ft (2.4 km) of altitude.

... a further link to this can be found here.

Good to see climbers actively involved in this new* game.
(*Though I recall climbers basejumping of cul-de-sac climbs in Yosemite back in the late70's/early'80s if I remember correctly).


Climboholic
20/12/2011
11:27:32 AM
To clarify, stalling doesn't mean coming to a momentary stop in the air. As explained earlier, it is a sudden drop in lift with increased AoA.

Stalling is bad, mmmkay. You never want to stall close to the ground because you'll drop like a stone.

The only way to come to a stop in the air is to have enough lift to pull up into a vertical climb so that all your forward motion is washed off by gravity. Gliders can do this and I think it is theoretically possible to do it with a wing suit if it was efficient enough (high lift, low drag). The challenge would be carrying enough speed to make a smooth arc to the vertical without stalling.
condor
26/01/2012
2:35:56 AM
Please could you tell me where I can get Full version incl impact.
Wollemi
25/05/2012
9:16:57 AM
'Five seconds before he hit the target he flared his suit to decrease his descent and glide angle before plunging into the boxes to break his fall.'
http://news.sky.com/home/strange-news/article/16233460

Found at SeaBreeze, where a couple of guys give their first-hand experiences of decking;
http://www.seabreeze.com.au/forums/General-Discussion/Chat/Skydiving-without-a-parachute/

 Page 2 of 2. Messages 1 to 20 | 21 to 39
There are 39 messages in this topic.

 

Home | Guide | Gallery | Tech Tips | Articles | Reviews | Dictionary | Forum | Links | About | Search
Chockstone Photography | Landscape Photography Australia | Australian Landscape Photography

Please read the full disclaimer before using any information contained on these pages.



Australian Panoramic | Australian Coast | Australian Mountains | Australian Countryside | Australian Waterfalls | Australian Lakes | Australian Cities | Australian Macro | Australian Wildlife
Landscape Photo | Landscape Photography | Landscape Photography Australia | Fine Art Photography | Wilderness Photography | Nature Photo | Australian Landscape Photo | Stock Photography Australia | Landscape Photos | Panoramic Photos | Panoramic Photography Australia | Australian Landscape Photography | Mothers Day Gifts | Gifts for Mothers Day | Mothers Day Gift Ideas | Ideas for Mothers Day | Wedding Gift Ideas | Christmas Gift Ideas | Fathers Day Gifts | Gifts for Fathers Day | Fathers Day Gift Ideas | Ideas for Fathers Day | Landscape Prints | Landscape Poster | Limited Edition Prints | Panoramic Photo | Buy Posters | Poster Prints